id,summary,reporter,owner,description,type,status,component,version,resolution,keywords,cc,guest,host 9053,FSTENV assembler instruction - wrong implementation,Franjo Stipanovic,,"Hi, I believe VirtualBox has wrong implementation of FSTENV assembler instruction. It is not dumping last float-pointing instruction address correctly. I've created a simple application in assembler which can be used as proof. Try and debug this application with debugger (OllyDbg for example) and take a look at buffer after the FSTENV instruction. It should contain address of FNOP assembler instruction. {{{ format PE GUI entry main include 'win32a.inc' section '.data' data readable writeable buffer db "" "", 0 section '.text' code readable executable main: nop mov eax, buffer fnop fstenv [eax] invoke ExitProcess, 0 section '.idata' import data readable library kernel32, 'KERNEL32.DLL' import kernel32, ExitProcess, 'ExitProcess' }}} You can compile the example code with FASM.",defect,closed,other,VirtualBox 4.0.8,obsolete,assembler implementation floating point,,Windows,Windows